The anatomy of a plant is shaped by cell walls that give the plant its
structural framework. Studying the framework of the plant will
help
you understand how it is organized and grows.

The illustrations on this page show details
of duckweed anatomy
that cannot be seen by casual observation.

The first two sections have diagrams
illustrating the relationships
among the fronds in a typical cluster. To understand these
diagrams
it is important to keep in mind that the duckweed plants consists of a
cluster of fronds descended from a single mother frond.

You can view the hidden framework inside a duckweed plant using a
simple
chemical treatment. [
Read
how. ]

Photo from Landolt, 1986, used with permission.Click on any image for a magnified view.

Details of a Lemna plant.

The pattern of asexual reproduction: As
each
new frond matures, it initiates the formation new fronds. Each
daughter
frond initiates as a bud in the meristematic zone
along the center axis of its mother. It then emerges from the pouch
on the side of the mother where it was initiated. Each new frond
is connected to its mother frond by a strip of tissue called a stipule
or stipe. The stipule elongates as the frond matures. When
the daughter frond reaches full maturity, the stipule breaks off to
release
a new cluster. By that time in rapidly-growing duckweeds, the
newly-released
frond has already initiated new daughters.

Flowers buds are also initiated in the frond
meristem,
but their formation is not required for unlimited asexual reproduction.

Interpretation of the Duckweed Frond:
Schematic Diagrams

Several plant anatomists have tried to interpret the anatomy of
the duckweed frond in terms of the anatomy of related higher plants,
from
which the Lemnaceae probably evolved. Elias Landolt has provided
the most convincing recent interpretation.

Legend: left, Spirodela, center, Wolffiella,
right, Wolffia.

The Lemna frond is organized very similarly to Spirodela,
but
there is no prophyllum at the base of the frond (the prophyllum at the
base of the flower is present in Lemna).

F0 mother frondF1 daughter frond of
the first
generationF2 daughter frond on
the second
generationa first frondb second frond (accessory
frond to
a)c third frond
(accessory frond
to b)